Transfer apparatus



April 10; 1945.

s. c. PLUMMER 2,373,413 TRANSFER APPARATUS Filed May 3, 1940 5Sheets-Sheet 2 INVENTOR JfUa/f p/ m QTMJMW ATTORNEY April 10, 194-5. 5.c. PLUMMER 2,373,413

TRANSFER APPARATUS Filed May 3, 1940 5 Sheets-Sheet 5 Tig /Z QM-rm .M

. ATTORNEY April 10, 1945.

s. c. PLUMMER TRANSFER APPARATUS Filed May 5, 1940.

5 Sheets-Sheet 4 INVENTOR .SfL/Q f C. P/ummcr ATTORNEY April 1945- s. c.PLUMMER 2,373,413

TRANSFER APPARATUS Filed May 3, 1940 5 Sheets-Sheet 5 III/III 4 ATTORNEYPatented Apr. 10, 1 945 TRANSFER APPARATUS Stuart C. Plummer,Wilmington, Del., assignor to All American Aviation, Inc., Wilmington,Del., a.

corporation of Delaware Application May 3, 1940, Serial No. 333,081

19 Claims.

This invention relates to aircraft pick-up and delivery apparatus.

In pick-up and delivery systems of the type to which the presentinvention relates, the burden to be picked up is disposed at a groundstation and a pick-up line or other device is attached to the burden andpositioned for engagement by a hook trailed from the aircraft by atransfer line. The aircraft is flown past the ground station in suchmanner that the hook engages the pick-up line and thereby picks up theburden.

The burden ordinarily is accelerated from a position of rest to thevelocity of the aircraft and hence, where the aircraft is traveling at ahigh rate of speed, as is usually the case, or the burden hassubstantial weight, the inertia which must be overcome and the shockswhich must be absorbed are very substantial. It is, therefore, desirableto provide shock-absorbing means so that the forces incident toaccelerating, the burden are not applied to, the aircraft or associatedapparatus in such a manner as to cause undue shock to or strain to theaircraft, its pick-up equipment or the burden to be picked-up.

It is also desirable that the hook be guided positively into engagementwith the pick-up line and that the transfer line to which the hook isattached be prevented from whipping about before and after the pick-upis effected.

In accordance with the present invention, the hook is suspended from theaircraft by a transfer line and the latter is connected to atake-updevice, such as a reel, for controlling the paying out or drawingin of the transfer line. There is associated with the transfer lineshock-absorbing means for absorbing at least a portion of the shockresulting from the initial engagement between the pick-up apparatus andthe pick-up line or other device at the ground station, which thepick-up apparatus is intended to engage.

The shock or energy absorbing device is particularly necessary toprevent breaking of the cable while the reel is being accelerated.Automatic braking means is associated with the reel which means iseffective, when the burden is engaged, to permit the transfer line topay out under controlled restraint or drag, the drag being graduallyincreased whereby to accelerate the burden and to gradually cause it toassume the velocity of the aircraft. There is also provided means forreleasing and adjusting the drag means and means controlling the reelfor'drawing in or paying out the transfer line.

An arm or other substantially rigid member, which is pivoted to theaircraft may be associvision in apparatus of the class described of a'ated with the transfer line for the purpose of positioning and guidingthe hook and for providing an additional initial shock-absorbing means.The arm is adapted to swing rearwardly when the initial contact withthe-pick-up line is made and is so positioned and dimensioned as topermit a movement of the hook relative to the aircraft greaterthan'corresponds to the paying out of the transfer line from the reel.

An object of the present invention is the provision of aircraft pick-upand delivery apparatus having improved means for absorbing the shockincident to a. pick-up operation.

Another object of the invention is the provision in apparatus of theclass described of a mechanism for automatically controlling the initialpaying out of'the transfer line to which the pick-up hook is attached.

Still another object of the invention is the prosimple, compact andrugged mechanism for absorbing at least a portion of the shock incidentto the pick-up operation, for paying out a predetermined length oftransfer line at a controlled rate and for controlling the drawing in orpaying out of the transfer line.

A further object of the invention is to provide a means whereby the rate,of acceleration of a burden picked-up may be controlled within limits.

A further feature of the invention is the provision in apparatus of theclass described of means for damping outthe shock transmitted to a reelat the time of pick-up and for accelerating said reel to make iteffective as an additional energy absorber.

Various other features and advantages of the I invention will beapparent from the following particular description and from aninspection of the accompanying drawings.

Although the novel features which are believed to be characteristic ofthis invention will K be particularly pointed out in the claims appendedhereto, the invention itself, as to its objects and advantages, and themanner in which it may be carried out, may be better understood byreferring to the following description taken in connection with theaccompanying drawings forming a part hereof, in which:

Fig. 1 is a somewhat diagrammatic side elevational view of an aircrafthaving associated therewith apparatus constructed in accordance with thepresent invention, the aircraft being shown diagrammatically in relationto one form of station constructed in accordance with the invention:

Fig. 2 is anenlarged fragmentary, side elevational view of themechanismfor drawing in or Fig. 4 is a somewhat diagrammatic viewshowing the aircraft of Fig. 4 and associated pick-up mechanism in itsposition after the burden has been pi ked up;

Fig. 5 is a somewhat diagrammatic view of the aircraft and associatedmechanism of Fig. 1 showing the transfer arm in retracted position Fig.6 is an enlarged fragmentary, front elevational view of the transferarm;

Fig. 7 is an enlarged fragmentary detail vie of the end portion of thetransfer arm;

Fig. 8 is an enlarged fragmentary, vertical cross-sectional view takenalong line 8-8 of Fig.

, Fig. 9 is an enlarged fragmentary, vertical cross-sectional view takenalong line 8-8, of Fig. 8';

Fig. 10 is a partially cross-sectional and partially diagrammatic view,the cross-sectional portion of the view being enlarged and taken alongthe line l-il of Fig. 8 and illustrating particularly the brakingmeansfor the gear motor, and the diagrammatic portion of the view beingreduced in size for convenience and showing the motor and control meanstherefor;

Fig. 11 is an enlarged fragment y. vertical cross-sectional view takenalong the line ll-i I of Fig.8, and

Fig. 12 is an enlarged, fragmentary view showing the connection betweenthe end of the transfer line and the reel.

In the following description and in the claims, various details will beidentified by specific names for convenience, but they are intended tobe as generic in their application as the art will permit. Likereference characters denote like parts in the several figures of thedrawings.

Referring now particularly to Fig. 1 of the drawings, there isassociated with anaircraft I of any suitable construction, a transferline 2 having attached to its putermost end a hook 3 for effecting apick-up. The transfer line 2 is suitably connected in the mannerhereinafter more fully described, to a control device 4 for controllingthe drawing in or paying out of the transfer line 2.

The transfer line 2 is guided by suitable mechanism hereinafterdescribed-adjacent the end of a transfer arm I by which arm the hook 3can be positioned and guided and which arm also serves as ashock-absorbing means as explained hereinafter. The arm 5 includes aprincipal portion II (see also Fig. 6) formed with a yoke I6 at itsinner end by which the arm is pivotally connected as by a Divot pin I Ito a bracket I8 attached to the aircraft preferably adjacent therearward'portion thereof.

The outer end of the arm 5 is constitutedby a section I! (see Figs. 6and 7 also) connected as by an elbow 20 to the main section I! forlimited angular or folding movement between a position asraus tached toa portion 2! of the transfer line 2 which isled into the outer end ofthe section I! and out through an opening 23; the transfer line 2 istrained around a sheave 2i suitably secured ad- I: iacent the opening23. The hook 3 may be provided with a closing latch 20 maintained inclosed position by a spring 28 to retain any line or other memberentering or engaged by the hook.

A burden release member 21 (Fig. 7) may be pivotally connected to theend section is and maintained in closed position thereagainst by atension spring 28. The burden release member 21 may be actuated by anydesirable means such as a burden release line 8 which is trained arounda sheave 29 adjacent the elbow and which line 6 terminates at a positionwithin convenient reach of the pilot or operator. An actuating member 8may be attached to the end of the burden release line 8 (see Fig. 1).

20 The present inventionmay be employed with any suitable type of groundstation, but for the purpose of facilitating a disclosure of theinvention, there is shown herein a groundstation l0 (Fig. 1) comprisingspaced poles Ii supporting quick releasing support clips l2 whichdetachably support a pick-up line 13 in position to be engaged by thehook 3 when the aircraft is suitably down past the ground station It. Aburden container 1 is attached to the pick-up line IS in a suitablemanner and may be supported in any suitable manner as by placing it onthe ground or on a platform H.

The control device 4 for paying out or drawing in the transfer line 2comprises generally a winch or reel 8!, an automatic brake 80 (see Fig.8) operative to place the maximum braking effort upon the reel upon apredetermined number of revolutions thereof, a motor I60 (Fig. 8) forrotating the reel, and a shock-absorbing device 5| (Fig. 2).

40 Referring now particularly to Figs. 2 and 8, the

control device includes a frame 50 which supports the reelii and theshock absorber 5]. The latter includes a shock strut of the air-oiltype, which may be of any ordinary construction, and which includes apiston 52 vertically slidable in a cylinder 53.

Carried at the upper end of the movable piston 52 and rigid thereto is across arm 54 having paired sheaves 55 freely rotatable on pivot pins 56at the ends of the cross arm; guides 51 preferably are associated withthe sheaves for preventing the associated line from being displaced.

A stationary cross arm 58, generally similar to the cross arm 54, isrigidly secured to the frame E0 and carries a sheave 59st each end.

The transfer line 2 is attached at one end to the reel 0|, preferably bya connection which will permit the end to be released in the event ofemergency. Referring to Fig. 12, the end of the 60 line 2 is secured ina socket 200 threaded on a o5 reelGl.

The transfer line 2 has a part 2a (see Fig. 2) extending upwardly fromthe reel GI and is trained successively around the sheaves 55 in arectangular path having the vertical parts 2b and 7 2c. The line has apart 2d extending downwardly I from the right hand upper sheave, pastthe reel ii and close to the periphery thereof. The transfer line 2 istrained around a guide sheave 60 rigidly mounted adjacent the bottom ofthe aircraft and the part 2e extends through a hatch 9 face of the brakedisc 8|.

in the bottom of the aircraft and to the sheave 23 (above mentioned)secured in the end section I8 of the transfer arm 6 (see Fi 1).

Referring now particularly to Fig. 8, the reel 8| is fixedly carried bya shaft 82 journaled at one end in a. bearing 88 mounted in the framemember 48 and provided with a seal 86 and a cover 68. The reel 8|includes a cylindrical rim 61 connected by a web 68 to a hub 88 andhaving at one end a retaining flange I I. A spirally grooved cylindricalsleeve I8 is positioned about the cylindrical portion 61 and issecuredvin position by a retaining flange I2 attached to the rim 61 asby bolts I3. The reel 8| is suitably secured against axial or angulardisplacement on the shaft 62 and abuts a positioning shoulder I4.

A brake plate I6 (Figs. 8 and 9) may be attached to and carried by thereel 8|. The brake plate I6 is provided with a plurality ofcircumferentially spaced lugs I8 which are set in notches 11 formed inlugs 18 which extend inwardly from the cylindrical portion 61. The plateI thus is capable of moving axially but is locked against angularmovement relative to the reel6I.

A brake 88 cooperates with the brake plate I5 and includes a drivingbrake disc or support 8I having a suitable friction lining 82 secured toits face and adapted to bear against the brake plate 15. The brake disc8| is carried by (and in the present embodiment, integral with) a hub 83which carries abearing 84 mounted on the shaft 62 and retained by a ring85.

The hub 83 has a journal-and-bearing portion 88 which receives a bearing88positioned by a ring 8|. A sleeve 88 abutting a. shoulder 88 on theshaft assists in positioning the bearing 88 on the shaft 82. The bearingand journal portion 88 is itself joumaled in a bearing 81 mounted in theside wall 48 of the frame 58 and secured by a ring 285. Thus the bearing81 constitutes, with the bearing 83. the main bearings for supportingthe shaft 82 rotatably in the frame 58.

Cooperating with the brake plate I5 and the brake plate disc 8| is adriven brake disc or shoe 82 of annular form having frictional lining 83on its face bearing against the brake plate I5. The brake discs 8| and82 are resiliently urged lightly toward the brake plate I5 by bolts 2|8each extending through the brake disc 82, the interior opening of thering I6 and through a suitable opening 2 in the brake disc 8| andcarrying a spring 2|2 bearing against the brake disc 8| and againstanadjusting nut or nuts 2I3.

Extending from the brake disc 82 is a plurality (in the present case 3)of studs 84 which extend through openings 88 in the brake disc 8|.Pivotally connected to each stud 84 by a pivot pin 86 is an operatinglever 86 which carries at the end of its shorter arm a roller 81 adaptedto bear against a boss 88 projecting from the adjacent The end of thelong arm of the actuating lever 86 is pivotally connected as by a pivotpin I88 to a socket I8I attached to an actuating rod I82 which extendsthrough the journal and bearing portion 86. The actuating rod I82 isconnected by a spring I83 to a stud I84 which is threaded into a discI86.

Upon movement of the disc I85 (effected in a manner hereinafter to bedescribed) in a direction away from the brake disc 8| (to the right asviewed in Fig. 8) the actuating rods I82 are moved in a similardirection to thereby rock the levers 88 in a clockwise direction causingthe rollers 81 to bear upon their respective bosses 88 and to clamp thebrake disc 82 and the brake plate I5 against the brake disc 8|. Owing tothe lug and notch connection between the brake plate 16 and the reel 8|,the brake plate is thereby permitted to shift axially and allow theclamping action to take place.

In order to cause the actuating disc I86 to move outwardly and to applythe brake 88 upon a predetermined number of revolutions of the reel 8|,an automatic brake actuating mechanism is provided which will now bedescribed.

The disc I86 is non-rotatably connected to the journal and bearingmember 88 by a stud 8 which extends through the disc I86 and is threadedinto the member 88. The disc I86 is mounted on acollar III having aflange I I2 at one end and a ring .I I3 at the other end, the disc I andcollar III being thus permitted to have relative axial sliding movementwhich is limited in extent by the flange H2 and ring H3.

The collar III is adiustably threaded onto an outer sleeve H4 and ispositioned non-rotatably thereon by a spring II6 adapted to enter intoany one of a plurality of circumferentially spaced, axially extendingnotches or slots I I6. The spring The inner sleeve II I is non-rotatablysecured totheshaft 62 as by a key I I8.

Movement of the sleeve 4 on the inner sleeve I I1 is limited by a flangeH8 at the inner end of the inner sleeve III and by a ring I28non-rotatably secured on the shaft 62 as by a key I2I and a nut I28 andabutting the outer end of the sleeve III. In order to permit axialmovement of the outer sleeve 4 on the inner sleeve III, a recess I24 isformed in the outer sleeve 4 of sumcient diameter to accommodate thering I28. For the purpose of manually turning the outer sleeve II4, aflange I22 is provided at its outer end and has sockets I28 for aspanner.

In order to provide a suitable braking action or drag on the outersleeve II4 to prevent it from rotating except when desired, a frictionbrake may be provided (see Figs. 8 and 11). The friction brake includesa brake ring I38 which surrounds the outer sleeve 4 and preferably seatsin a circumferential groove I34 to prevent dis- I placement of the ringI38. The brake ring I38 may be of the split ring type, the tension ofwhich may be adjusted .by a nut I32, a suitable brake lining I33 beingprovided. The brake ring I38 is formed with a lug or extension |3|having an opening I36-through which the stud I I8 passes whereby thebrake ring I38is non-'rotatably connected to the member 88.

It will now be seen that upon rotation of the shaft 82 which carries thereel 8|, the inner sleeve I I1 is rotated correspondingly and throughthe action of its threads causes the outer sleeve 4 to be moved axiallyand that by providing suitable direction to the threads on the sleevesH4 and III the sleeve 4 will be moved in a direction away from the framemember 48 (to the right, as viewed in Fig. 8). As the outer sleeve 4moves outwardly, the flange H2 is brought into abutment with the discI85 and moves it in a corresponding direction, thereby exerting a pullon the several actuating rods I82 and causing the brake disc 82 and thebrake plate 18 to clamp more tightly against the brake disc 8|. Thebrake 88 therefore is automatically applied with continuously increasingforce until the reel 8I is halted or until the end of the socket orrecess Inordertorotate the reel soastodrawin or pay out the transferline 2, suitable rotating means are provided, which in the present case,comprise a driving motor I88 connected to the brake 88.

Referringnow particularly to Figs. 8 and 9, a drive gear I88 is rigidlysecured to the brake disc 8| as by bolts IN and a driving, pinion I82meshes with the gear I88. The driving pinion is carried on a shaft I 88joumaled in a bearing I84 secured in a portion of the frame member 48 asby a ring I88 and sealed by a seal I81.

The shaft I88 constitutes also the shaft of a motor I 88 and extendsinto the housing I88 of the motor which is secured to a bracket forminga portion of the frame member 48. The housing is closed by an end plateI88 and the shaft sealed therein by a seal IN. The motor may be oi anysuitable constructionto be operated by iiuid pressure and may, forexample, include a gear I82 carried on the shaft I88 meshing with a gearI88 carried on a shaft I84 iournaled in the housing I88.

In order to lock the shaft I88 of the motor I88 against rotating andconsequently prevent rotation of the gear I88 and the brake 88, a brakeI88 is provided. This brake includes a drum I81 no'n-rotatably securedto the shaft I88 as by a key I88 and having a band I88 anchored as atI88 and extending around the drum I81. The band I88 enters a socket I10and ispivotally connected by a pivot pin I12 to a bell crank lever I1Ipivoted at I18 and pivotally connected as at I14 to a rod I18 attachedto a piston I18 slidable in a cylinder I11 of a brake actuating deviceI88. The piston I18 is normally ,urged into its lower and exhaustposition by a spring I18 bearing against a plate I18 secured to thecylinder I11, the brake thereby being normally applied.

The motor I88 and brake actuating device I88 just described are actuatedand controlled by a fluid system, such as an oil system, receivingpressure through a supply pipe I82 from a suit-. able pressure source(not shown) The supply pipe I92 leads to a valve I8I actuated by ahandle I82 which valve is connected through pipes I83 and I84 with themotor. A discharge pipe I88 leads from the valve I 8|.

The valve I8I can be adjusted so that the pipe I88 is connected to thesupply pipe I82 and the other pipe I84 is connected with the dischargeconduit I88; in this position the gear motor I88. is driven in onedirection. The valve handle I82 can, alternatively be adjusted toanother position wherein the pipe I84 is connected to the supply pipeI82 and the pipe I88 is connected to the discharge pipe I88 where- -uponthe motor is driven in a reverse direction.

The valve I8I can also be set at closed position, as illustrated in Fig.10.

The supply pipe I82 also leads to a valve I81 controlled by handle I88.The valve I81 is con- .nected by a pipe III to the interior of the cyl-'inder I11, whereby when the valve is set in one position, fluid underpressure is admitted to the cylinder I18. A discharge pipe "I leads fromthe valve I81 whereby the cylinder I11 can be exhausted.

It will further be understood that by'adiusting the nut or nuts 2" theinitial tension on the spring 2I2 may be adjusted and consequently thefrictional resistance between the brake plate 82, brake disc 18, andbrake plate II can be set.

Furthermore, by adjustment of the collar I II the number of turns of thereel which will be required to set the brake 88 may be controlled.Similarly the amount of cable which may be paid out before the brake isfully set may be adjusted. Thus :by proper adjustment of the initialtension on the springs 2I2 and the positioning of the collar III theaccelerating effect of the brake on the reel 8i and consequently theacceleration on the burden to be picked up can be controlled withinlimits.

The operationof the apparatus is as follows when a pick-up and deliveryis to be made:

In normal flight the transfer arm 8 will be in retracted position asillustrated in Fig. 5. The burden 1.1: to be delivered is attached tothe arm 8 by the burden release member 21. The valve I81 (Fig. 10) isoperated to release the motor brake I88 and the valve I82 is actuatedsuitably to operate the motor in a direction to pay out the transferline 2. The arm 8 thereupon swings downwardly and rearwardly(counter-clockwise as viewed in Figs. 1, 4, and 5) and the arm 8 ishalted in a position slightly inclined rearwardly from the. vertical, asillustrated in Fig. l.

The aircraft is then flown toward the ground station It (Fig. 1) andpreferably prior to reaching the posts I, the actuating member 8 for theburden release line 8 is operated to open the bur- 1 den release member21 to allow the burden 1x to be dropped to the ground.

The aircraft is caused to fly at such height that the horizontal partIla oi the ground loop I8 is engaged by the part 20 of the transfer line2, or by the arm 8, or by the hook 8. The initial impact between thepick-up apparatus carried by the aircraft and the pick-up line i8detaches the latter from the clips I2 and places an initial tension onthe transfer line 2. This initial tension may start the movable crossarm 84 downwardly against the resistance of the shock strut 8| dependingupon the adiustment of the strut.

The ground loop I8 slides down along the part 2e of the transfer line 2and along the arm 8 and into engagement with the hook 8. The inertia ofthe burden 1 places the transfer line 2 under tension and furthercompresses the shock strut II. The movement of the upper cross arm 84downwardly, however, permits the pick-up line 2 to be payed out a lengthapproximately equal to four times the distance between the upper andlower position of the movable cross arm 84 against the constantlyincreasing resistance offered by the shock strut 8I. Thus the tensionapplied to the transfer line 2 by the inertia of the burden 1 isgradually applied to the ply 2a. and thereby applied to the reel 8I' tostart it in motion, and the shock which would otherwise be transmittedthrough the transier line 2 is damped out.

When a suflicient tension is applied to the ply 2a of the transfer line2 to initiate rotation of the reel 8i (see Fig. 8), it rotates againstthe relatively light friction applied to the brake plate 15 by thespring or springs 2I2 acting upon the brake disc 8| and the brake disc92.

Rotation of the reel BI causes a corresponding rotation of the shaft 62and the inner sleeve II'I, thereupon causing the outer sleeve I I l tobe moved axially in a direction away from the brake 80. This movementcauses the brake disc 92 to be urged to bear with increasing force uponthe brake plate I5 and it in turn upon the brake disc 8| and therebyapply increasing drag or resistance upon the reel 6| to gradually retardits rotation.

Before the end of the recess I24 strikes the ring I20, the reel GI' mayhave been halted and the burden I accelerated to the same velocity asthe aircraft. During the action of applying the brake, the brake disc 8I, and accordingly the cooperating brake disc 92, are held againstrotation, by the engagement between the gear I50 and the pinion l52,which latter is locked against rotation by the brake I66 (see also Figs.10 and 11).

It will be understood that when the transfer line 2 is payed out, thehook 3 moves away from its seat in the end of the transfer arm 5 anddrawsthe transfer line through the end section I9 of the arm. If it isdesired to pay out the transfer line 2 more than it is payed out by therotation of the reel BI as above described, the motor ISO is suitablyoperated. Ordinarily, however, the transfer line 2 will be payed outsufficiently by the action of the shock strut SI and associated members,the rearward swinging of the arm 5, and the rotation of the reel 6 I'relative to the brake 86.

When the brake 80 has been applied to halt the reel 6 I, the shock strutwill usually (if it has not previously done so) extend under theinfluence of the air compressed therein and will move the cross arm 54to its upper position. However, in the event that the shock strut is setfor very "soft operation wherein the resistance to collapsing movementis relatively light, the shock strut may remain collapsed as long as theburden T is being dragged behind the aircraft.

After the burden I has been accelerated to the speed of the aircraft,the valve I81 (see Fig. 10) is operated to release the brake I66 and thevalve I8I operated to energize the motor and rotate the pinion I52 andgear I56. Since the brake 80 remains applied to the reel BI, the reel BIis rotated and winds in the transfer line 2 until the hook 3 reaches theend of the transfer arm I5 and the shank 22 of the hook enters the endof the outer end section I9. Further rotation of the reel BI' causes thearm 5 to be rotated forwardly (clockwise as viewed in Figs. 1, 4 and 5)to bring the end of the arm adjacent the hatch 9 and'finally to turn theend section I9 about its pivot so that it enters the body of theaircraft and brings the pick-up line I3 into position to be removed fromthe hook 3.

In order to reset the brake operating mechanism, a spanner (not shown)is inserted in the openings I25 of the outer sleeve II I (Fig. 8) andthe latter rotated in a suitable direction so that it is moved inwardlythereby releasing the brake 80 and leaving the reel 6| relatively freeto rotate when the next pick-up is made.

It will be understood that while a pick-up and delivery operation hasbeen described, the apparatus is suitable for carrying out either ofthese operations independently, as well as at approximately the sametime. In certain cases, as will be understood, it may be desirable tomake a of natural or artificial fibres or strands or metal cables orother suitable materials.

It is to be understood that the several portions of the apparatus otherthan the brake linings will Ordinarily be formed of metal of suitablecomposition, and' wherever possible, they will be formed of lightweightmetal, as for example, aluminum or aluminum alloys. All parts, ofcourse, will be constructed of a material of sumcient strength, rigidityand wear resisting characteristics to perform the-desired functions andto provide satisfactory life.

While certain novel features of the invention have been disclosedherein, and are pointed out in the annexed claims, it will be understoodthat various omissions, substitutions and changes may be made by thoseskilled in the art without fldeparting from the spirit of the invention.

What is claimed is:

1. The combination with an aircraft of means for picking-up burdenswhile said aircraft is in flight, said means including a reel, a shockstrut associated with said reel, a pick-up arm pivotally connected tosaid aircraft adjacent the rearward portion thereof, a guideway and aseat in said transfer arm, a transfer line attached at one end to saidreel and trained over said shock strut and non-disengageably through theguideway in said pick-up arm, a hook connected to the other end of saidtransfer line andpositioned in said seat, whereby reeling in said lineoperates to swing said arm to inoperative position.

2. The combination with an aircraft of means for picking-up burdenswhile said aircraft is in flight and for reducing the shock and strainto said aircraft and said burdens incident to said pick-up, said meanscomprising a rotatable reel, a transfer line attached at one end to saidreel, a hook attached to the other end of said transfer line, said hookand transfer line adapted to engage a burden to be picked-up and tocause said reel to rotate, means including a shock dampening deviceassociated with said reel and said transfer line and adapted to relievethe strain on said transfer line while said reel is being accelerated,automatic brake applying means adapted to be actuated by rotation ofsaid reel, said brake applying means including means for progressivelyincreasing the force of the brake to a predetermined maximum, and apick-up arm pivotally connected to said aircraft adapted to guide saidtransfer line and seating said hook.

3. The combination with an aircraft of atransfer line, a reel carried bysaid aircraft for drawing in and paying out said transfer line, a hookattached to said transfer line, automatic braking means associated withsaid reel and operative to halt said reel upon the drawing out of a predetermined length of transfer line, a transfer arm pivotally connectedto said aircraft and having at least a portion exteriorly thereof, meanscarried by said arm for holding and positioning said hook, and anair-oil shock dampener associated with the part of the transfer lineintermediate said reel and said hook.

4. The combination with an aircraft of means for picking-up burdenswhile said aircraft is in flight, said means including a reel, 9. line,means attaching said line to said reel, said means adapted to break whena predetermined load is placed thereon, a hook attached to said line,means associated with said reel and said line adapted to absorb a partof the energy transmitted through said line to said reel upon contact ofsaid hook with a burden to be picked up and operative to reduce thestrain to said line when said burden is picked up, said means forabsorb-' ing a part of said energy comprising a shock strut said shockstrut having spaced supports yieldably held apart, a plurality ofsheaves journaled on said supports, said line trained over said sheavesto form a plurality of plies whereby. when a strain is placed on saidline, said shock strut will be compressed in lesser amount than theamount of line which will be permitted to pay out when the strain isplaced thereon.

5. In an automatic winch for airplanes and the like, a frame, arotatable support journaled in said frame, a drum also journaled in saidframe, spring devices operating between said support and drum forexerting constant initial light friction on said drum, devicescontrolled by rotation of said drum for increasing the frictionalpressure between said support and said drum to a'predetermined maximum,and means for thereafter maintaining the pressure substantially constantat said maximum during continued rotation of the drum.

6. In an automatic winch for airplanes and the like, a frame, arotatable support journaled in said frame, a drum also Journaledin saidframe, devices operatively connected between said support and drum forexerting friction on said drum, means operating between said drum andsaid support for increasing the friction between said support and saiddrum to a desired maximum force, means for adjusting said means tochange the value of said maximum force, and means for adjusting saidmeans to change the number of relatively free revolutions before maximumforce is applied.

7. In a pick-up system for picking up a burden from a moving craft,devices for establishing connection between said craft and burden, saiddevices comprising a winch having a drum, a line wound on said drum anda pick-up device connected to said line, a brake support having a brakesurface, said brake surface having light frictional engagement with saiddrum, means controlled by the number of revolutions of said drumrelative to said brake support for increasin the friction between saidbrake support and drum to maximum braking pressure, a source of powerfor driving said support, means for connecting or disconnecting saidsource and said support, a brake for holding said support stationarywhen said source is disconnected, and an air-oil shock dampenerassociated with said line between the pick-up device and the drum, saiddampener permltting increase in the effective length of said l nebetween the drum and pick-up device independent of the unwinding of saiddrum.

8. In a pick-up system for launching a burden from a moving craft.devices for establishin connection between said craft and burden, saiddevices comprising a winch having a drum, a line wound on said drum anda pick-up device connected to said line, a brake support having a brakesurface engageable with said drum, said brake support permittingrelatively free rotation of said drum, means controlled by rotation ofsaid drum for gradually increasing frictional engagement between saidsupport and drum, a source of power for driving said support, and anelastic device associated with said line between the pick-up device andthe drum:

9. In an automatic winch for airplanes and the like, a frame, a reelrotatably mounted in said frame, a support rotatably mounted in saidframe, said support comprising a main brake disc and an adjustable brakedisc, 9, third brake disc secured to the reel and disposed between saidfirstmentioned brake discs, adjustable spring means for adjusting theinitial tension between said brake discs, an inner threaded sleeverotatable with said reel, an outer threaded sleeve rotatable with saidsupport, an adjustable collar threaded on said outer sleeve, said collarhaving an abutment, a ring surrounding said collar, brake applyinglinkage secured to said support, springs connecting said linkage andsaid ring, an auxiliary brake device operating between said support andsaid outer sleeve to prevent accidental rotation of said outer sleeve,said outer sleeve being adjustable with respect to said support and tosaid inner sleeve to adjust the maximum increase in tension applied tothe winch, said collar being adjustable on said outer sleeve to limitthe number of relatively free revolutions of said winch.

10. In an automatic winch for airplanes and the like, a frame, a reelrotatably mounted in said frame, a support rotatably mounted in saidframe, said support comprising a main brake disc and an adjustable brakedisc, a third brake disc secured to the reel and disposed between saidfirst-mentioned brake discs, an inner threaded sleeve rotatable withsaid reel, an outer threaded sleeve rotatable with said support, anadjustable collar threaded on said outer sleeve, said collar having anabutment, a ring surrounding said collar, brake applying linkage securedto said support, springs connecting said linkage and said ring, meansoperating between said support and said outer sleeve to preventaccidental rotation of said outer sleeve, said outer sleeve beingadjustable with respect to said support and to said inner sleeve toadjust the, maximum increase in tension applied to the winch, saidcollar being adjustable on said outer sleeve to limit the number ofrelatively free revolutions of said winch.

11. In an automatic winch for airplanes and the like, a frame, a brakesupport journaled in the frame, a drum also journaled in said frame,

a. line wound on said drum, a main brake operating between said supportand drum, brake applying mechanism operating between said drum and saidsupport for gradually increasing friction of said main brake, said brakeapplying mechanism including a control member movable from an initialposition to a final position, said control member when in its initialposition causing said brake to exert little or no friction on said drum,said control member when moving from initial to final position, causingsaid brake to exert gradually increasing friction on said drum, saidcontrol member, when in its final position causing said brake to exertsubstantially constant relatively high friction on said drum,controllable means for driving said brake support, means for holdingsaid brake support stationary when said drum is unwinding under forceapplied by said line.

12. In an automatic winch for airplanes and the like, a frame, a brakesupport journaled in the frame, a drum also journaled in said frame, aline wound on said drum, a brake operating between said support anddrum, brake applying mechanism operating between said drum and saidsupport for gradually increasing the friction of said brake, said brakeapplying mechanism including a control member movable from an initialposition to a final position, said control member, when in its initialposition, causing said brake to exert relatively light friction on saiddrum without substantially impairing the ability ofsaid drum toaccelerate when unwinding force is applied to said line, said movablecontrol member, when moving from initial to final position, causing saidbrake to exert gradually increasing friction on said drum, said controlmember, when in its final position, causing said brake to exertsubstantially constant relatively high friction on said drum,controllable means for driving said brake support in either direction,means for holding said brake support stationary when said drum is ing ashock absorbing operation, the parts of the winch being so arranged thatsaid main brake applies suilicient light friction to said drumto put itunder control of said winch motor but not suiilcient to preventrelativel free, rotation of the drum at the beginning of a shockabsorbing operation, said brake operating nut and screw graduallyincreasing the force exerted by said main brake on the drum as thelatter is unwound by said line during a shock absorbing operation, saidgradual increase continuing until the brake operating nut has reachedits final position after which the force applied to. said drum by saidmain brake remains constant at the adjusted maximum value.

15. In an automatic winch for airplanes and the like, a frame, arotatable support journaled unwinding'under force applied by said line,and I frame, a line wound on said. drum, a rotatable brake supportiournaled in said frame, said drum and brake support carrying sets ofbrake elements sandwiched together and constituting a main brake, oneset being attached to said drum and the other set being attached to saidbrake support, radial fingers pivoted to said brake support for applyingpressure to said sandwiched brake elements, a brake operating screwrotatable with said drum, a brake-operating nut on said screw andmovable lengthwise thereof during a shock absorbing operation from aninitial position to a final position, a brake applying linkageconnecting said nut and said radial fingers for controlling said mainbrake, adjustable means for adlusting the maximum pressure applied tosaid fingers by said linkage, a gear secured to said brake support, adrive shaft journaled in said frame, a pinion on said drive shaftmeshing said gear, a winch motor for driving said drive shaft, and amotor brake for holding said drive shaft stationary during a shockabsorbing operation.

14. In an automatic winch for absorbing the shock incident toaccelerating a load by an aircraft in flight, a frame having spacedbearings, concentric main shafts rotatably mounted betwegis saidbearings, a drum afllxed to one of said sha a line wound on said drum, arotatable brake support afllxed to the other of said shafts,

said drum and brake support carrying sets of brake elements sandwichedtogether and constituting a main brake, one set being attached to saiddrum and the other set being attached to said brake support, radialfingers pivoted to said brake support for applying pressure to saidsandwiched brake elements, a brake operating screw rotatable with saiddrum, a brake-operating nut on said screw and movable lengthwise thereofduring a shock absorbing operation from an initial position to a finalposition, a brake applying linkage connecting said nut and said radialfingers for controlling said main brake, adjustable means concentric ofsaid main shafts for adjusting the maximum pressure applied to saidfingers by said linkage, a gear secured to said brake support, a driveshaft journaled in said frame, a

pinion on said drive shaft meshing said gear, a winch motor for drivingsaid drive shaft, a motor brake for holding said drive shaft stationarydurin said frame, a drum also journaled in said frame, said supportbeing frictionally engageable with said drum, devices operativelyconnected with said support for exerting initial friction on said drum,threaded means operatively connected with said drum and said support forgradually increasing in accordance with the pitch of said threaded meansthe friction between said support and said drum to a predeterminedmaximum, means for discontinuing the operative connection of saidthreaded means, a controllable brake. for holding said support, andcontrollable means for driving said support.

16. In an air launching system, an aircraft, an object to be launched bysaid aircraft, apparatus establishing connection between said aircraftand said object comprising a winch having a drum, a line wound on saiddrum, said winch comprising a frame, a rotatable support rotatablymounted on said frame, said drum being rotatably mounted on said frame,said support being frictionally ing operation, and controllable meansfor rotat-- ing said drum to wind up said line. Y

17. In an air launching system, an aircraft, an object to be launched bysaid aircraft, apparatus establishing connection between said aircraftand said object comprising a winch having a drum, a line wound on saiddrum, a brake support having a brake surface engageable with said drum,

said brake support permitting relatively free rotation of said drum,means controlled by the rotation of said drum for gradually increasingfrictional pressure between said brake surface and said drum, acontrollable brake for holding said support'stationary during launchingoperation, and controllable means for rotating said drum to wind up saidline.

18. In an automatic winch for aircraft and the like, a frame, a drumjournaled in said frame, a line wound on said drum, said drum beingrotatably mounted on said frame, devices for exerting initial lightfriction on said drum to hold it stationary at the beginning of thelaunching operation, means controlled by the rotation of said drum forgradually increasing the frictional pressure exerted on said drum to apredetermined maximum to minimize shock on said line, means forretaining said predetermined maximum pressure at a constant value tocomplete the launching operation and controllable means for rotatingsaid drum to wind up said line.

19. In an air launching system; an aircraft; an object to be launched bysaid aircraft; apparatus establishing connection between said aircraftand said object comprising a winch having a drum;

a line wound'on said drum; said winch compris-' 'ing a frame; said drumbeing rotatably mounted on said frame; retarding means for said drum;said retarding means comprising, means for preventin payout of the lineprior to the establishment of connection between said aircraft and saidobject, means for applying frictional pressure to said drum, said meansfor applying frictional pressure being controlled by the rotation ofsaid drum to gradually increase the frictional pressure exerted on saiddrum from a relatively small amount to a predetermined maximum tominimize shock on said line, and means for retaining said predeterminedmaximum pressure at a'constant value to complete the launchingoperation; and controllable means for rotating sai drum to wind up saidline. STUART C. PLUMMER.

